Rotary pump



Jan. 18, 1966 P. R. L. RouDAuT ROTARY PUMP 2 sheets-sheet 1 4 Filed June 5, 1963 Pfl/LIPPE R. l.. ROUDAUT Jan. 18, 1966 P. R. 1 RoUDAUT 3,229,643

ROTARY PUMP Filed June 5, 1963 2 Sheets-Sheet 2 C M51/ f 4 4X/ff@ Md Inventor PHIL/PPE R. l.. ROUOAUT United States Patent 3,229,643 ROTARY PUMP Philippe Robert Louis Roudaut, 47 Ave. Ferdinand Buisson, Paris 16, France Filed June 3, 1963, Ser. No. 284,929

Claims priority, application France, June 12, 1962,

900,416, Patent 1,335,006

Claims. (Cl. 10S- 149) This invention relates to hydraulic pumping apparatus and more particularly to rotary pumping devices which are particularly suited to the pumping of abrasive fluids.

Alternating pumps whose suction and delivery charnbers are isolated from the pump mechanism by diaphragms are generally utilized to pump abrasive fluids. In operation, the alternating deformation of the pump diaphragms causes the volumes of the suction and delivery chambers to change, the fluid being introduced and then forced from the chamber in the desired direction of displacement by a system of valves. Such pumps have the disadvantage of providing a pulsating output. This disadvantage is usually overcome by the use of pressure absorbers or accumulators. Alternating pumps, though, have the additional disadvantages of being heavy and expensive, and their speed is often limited by the inertia of the valves utilized and even by the inertia of the diaphragms. While this latter disadvantage does not appear in continuous-flow volumetric pumps, such as vaned, gear-driven, or screw-type pumps, other problems such as effective sealing are present which are difficult to overcome.

It is, therefore, an object of the preent invention to privide a pump which is superior to prior-art pumps.

A further object is to provide a pump whose mechanism is completely isolated from the fluid being displaced.

A still further object is to provide an alternating pump capable of continuous operation and substantially free from pressure pulsation at the output thereof.

Yet another object is to provide a pump, the flexible, longitudinally disposed diaphragms of which may be pressurized to regulate the pump output.

A feature of this invention is the utilization of an annular chamber located between the body of the motor and a tubular diaphragm, which chamber is longitudinally subidivided by flexible partitions. A diaphragm surrounds a rotor which has a plurality of eccentrically mounted bearings disposed lengthwise of the rotor shaft and angularly staggered relative to one another. The motion of the eccentrics imparts a wavelike motion to the diaphragm lengthwise of the pump.

Another feature is the utilization of bearings made of rings having about the same maximum cross-sectional dimension as the diaphragm, which are mounted on eccentrics which in turn are keyed to a central shaft. When the shaft rotates, the eccentrics also rotate within the bearing rings causing a radial component of motion to be applied to the diaphragm in a substantially frictionless manner.

Still another feature is the utilization of an auxiliary shaft which communicates interiorly of the deformable diaphragm so that fluid under pressure may be introduced whereby the output of the pump is regulated.

The above-mentioned and other features and objects of this invention will become more apparent by reference to the following description taken in conjunction with the accompanying drawings, in which:

FG. 1 is a diagrammatic View showing the longitudinal section of a pump according to the invention;

FIG` 2 is a section of II-II of FIG. l; and

FIG. 3 is a section of III-III of FIG. l.

Basically, the pump of the present invention comprises a cylindrical body, crossed longitudinally by a tubular diaphragm forming with this body an annular chamber, one end of which communicates with an inlet orifice and the other with an outlet orifice for a fluid. Means are provided for continuously deforming the diaphragm thereby causing displacement, from the inlet orifice towards the outlet orifice, of the volume of fluid trapped between the diaphragm and the tubular body.

The mechanism which deforms the diaphragm is completely isolated from the fluid, and continuous operation without any pulsation at the output is provided. The sealing problems mentioned hereinabove are resolved as Well as the problems of speed limitation, since the offset rings ensure a positive readjustment of the diaphragm at each revolution of the shaft.

In the instance of high pressures operation, it is possible, by means to be described in what follows, to operate the rotor in a liquid which can circulate under pressure inside the diaphragm. By varying this pressure, the output of the pump can be effectively regulated.

In the embodiment shown in FIG. 1, the pump comprises a tubular body 1, connected near its extremities with pipes 2 and 3 which form respectively an inlet and outlet for the liquid to be conveyed- The extremities of the body 1 are closed by flanges 4 and 5 which, for instance, can be screwed on to the said extremities. Flanges 4 and 5 are also used to retain the ends of diaphragm 6 which has a smaller diameter than the body 1 and is made of some flexible material, such as rubber or synthetic plastic.

The ends of the diaphragm 6 are tightened between the extremities of body 1 and the bottom of the cavities of the flanges 4 and 5 in which these extremities are engaged; thereby preventing the fluid which is being pumped from entering internally of flexible diaphragm 6.

The flanges 4 and 5 have respective bosses 7 and 8 on their inside surfaces, over which the ends of diaphragm 6 are positioned to extend beyond the respective places where pipes 2 and 3 are connected to body 1.

Each boss is hollow and contains a bearing 9 or 1t) for a longitudinal shaft 11. Bearing 9 of boss 7 is a thrust bearing held in axial alignment by means of a shoulder 12 on the boss.

Eccentrics 13a, 13b, etc., are keyed on to the shaft 11 and they can rotate in joint rings 14a, 14h, etc., having an outside diameter almost equal to the inside diameter of the diaphragm 6. The ecentric 13a and the corresponding ring 14a, situated nearest to the inlet tubulation, are shouldered and act as thrust members for the various rings.

The eccentrics 13a, 13b, etc., have such an eccentricity that the diaphragm is brought substantially into contact with the interior surface of body 1 at the point of maximum radius. They are mounted lengthwise of and staggered angularly in relation one to another on shaft 1 1 in a regular way from one end to the pump to the other, so that the diaphragm 6 when deformed by rings 14a, 1411, etc., appears to be like a wide-threaded screw.

Referring now to FIG, 2, the annular space provided between diaphragm 6 and body 1 is divided longitudinally between the inlet and outlet pipes 2 and 3 into several cavities by flexible partitions, which in the present example are preferably constituted by a tube 15 made of the same material as the diaphragm 6; this tube has almost a square section and is fixed at each corner to the body 1 on the one hand, and at the midpoint of each side to the diaphragm 6 on the other hand.

Body 1 has longitudinal grooves 16 in which the corners of the tube 15 are receivable and are held in place by rods 17 similar to piano wire, for example. Grooves 19 in body 1 are adapted to receive the ends of rods 17. Rods 17, in turn, are retained by flexible split rings 1S. Rings 18 are receivable in grooves 19 such that axial movement of the ring 18 is prevented.

The grooves 16 can be either parallel with the axis of body 1 or slightly inclined in relation to this axis.

The tube 15 is fixed at the midpoint of the sides thereof to diaphragm 6 by means of a plastic joining material or other means well known to those skilled in the art.

FIG. l shows a means for mounting shaft 11 which is driven Iby a submerged rotor motor, shaft 20 of the motor is shown connected to shaft 11 by means of a semiflexible coupling 21.

Shaft 11 protrudes from flange 4 through a sealing joint 22 to be coupled at 23 to a normal motor.

The flange 5 has an aperture 24 which allows a liquid to be introduced under pressure and passed by a channel 25 into the inside cavity of diaphnagm 6. The venting of the air and also the flow of the liquid commence through duct 271-(FIG. 3) and channel 28 (FIG. l) disposed in flange 4 and terminated at an outlet 29. Further, a pressure gauge connection is provided in flange 5.

As shown in FIG. 3, boss 7 situated relative to the inlet tubulation 2, has 1an 4asymmetrical cross-section so that there is a wider passage for liquid as it leaves pipe 2, in the direction indicated by arrow f.

The pump just described operates as follows:

When the rotor is put into rotation, in the direction indicated by arrow f on FIG. 3, the various cavities 15 arranged between the body of the pump and the tube 15, as well as those between this tube and the diaphragm 6 undergo deformations, in response to the action of eccen- 'trics 13a, 13b, etc., so that the jet of liquid found in each of the said cavities 15 is progressively thrust from the space facing the inlet pipe 2 up lto the space where the outlet pipe 3 commences, As a result of the successive 'deformation of the various cavities both axially and circumferentially about the axis of the pump, the displacements of the resulting jets of liquid succeed each other regularly and the pump operates continuously, without any notable pulsations.

lf the pump is required to operate under low p-ressure, it is not necessary to pass the liquid through the pipe 24.

For operation under high pressure, it is preferable to pass through this pipe, 1a liquid under pressureto prevent crushing the diaphragm 6 against the rotor. Such a liquid which can be called a shock absorbing liquid or a controlling liquid, allows diaphragm 6 to be further expanded and therefore acts on the output by reducfing the difference between the maximum and minimum .effective radius of the eccentrics, the output being re- A.duced as the pressure of the controlling liquid is higher.

To obtain a high output, the suction and delivery spaces can be equipped with guide-vanes which facilitate the flow of the liquid being pumped.

The body of the pump, as Well as the tube and diaphragm, should be made with a material able to resist the liquid to be conveyed; if necessary, a coating should -rbe applied .Q the inside casing of the body of the pump.

This last item can be equipped with a lining to permit the circulation of a heating or cooling fluid, as required.

While I have described the principles of my invention in connection with specic apparatus, it is to be lclearly understood that this description is made only by way of example and not ias a limitation to the scope of my inven- -tion as -set forth in the accompanying claims.

claim:

1. A rotary pump for a fluid, comprising a cylindrical tu'bula-r body which is longitudinally traversed by a flexible tubular diaphragm defining with this body an rannular chamber, the respective ends of which communicate with an inlet and an outlet orifice for a fluid, means for continuously deforming the diaphragm to cause the displacement, from the inlet orifice towards the outlet orifice, of fluid confined between the diaphragm and the tubular body, and further characterized in that said means for deforming the diaphragm are constituted by an helicoidal rotor having a circular section and a series of bearings eccentric in relation to the axis of the pump body, said bearings being angularly staggered, and said diaphragm resting on rings in which the eccentric bearings of the rotor can rotate.

2. Pump as claimed in claim 1, including also flexible partitions, the `annular chamber between the diaphragm and the tubular body being longitudinally divided between the inlet orifice and the outlet orifice by said flexible partitions fixed t-o the inner surface of said cylindrical tubular body.

3. A rotative pump comprising a tubular body, said tubular body having a rigid wall, a flexible wall, said flexible wall being disposed internally of said tubular body and being sealed at its extremities to the extremities of the interior of said tubular body, thereby defining a substantially annular chamber, inflow and outflow ports disposed adjacent the respective extremities of said tubular body to convey fluid to and from said annular chamber, a plurality of flexible partitions, each of said partitions being connected at the longitudinal edges thereof to said rig-id wall of said tubular body and at its midpoint to said flexible wall and extending longitudinally of said tubular body, thereby forming a plurality of cavities within said substantially annular chamber, and eccentric means disposed axially of said tubular body for deforming said flexible wall by applying successive radially directive forces to said flexible wall to generate a wave-like motion in said flexible wall from one of said ports to the other of said ports.

4. A rotative pump comprising a tubular body, said tubullar body having a rigid wall, a flexible wall, said flexible wall being disposed internally of said tubular body and being sealed at its extremities to the extremities of the interior vof said tubular body, thereby defining a substantially annular chamber, inflow and outflow ports disposed adjacent the respective extremities of said tubular body to convey fluid kto and from said annular chamber, a tube disposed intern-ally of said tubular body, said tube being attached at a plurality of points to the inner surface of said rigid wall of said tubular body, and being attached at a plurality of other points to the surfaces of said flexible wall, thereby defining a plurality of cavities between the portions of ysaid tube and said rigid Wall and between portions of said tube and said flexible wall, and eccentric means disposed axially of said tubular body for deforming said flexible wall by applying successive radially directive forces to said flexible wall to gene-rate a wavelike motion in said flexible Wall from one of said ports toward the other of said ports.

5. A rotative pump comprising a tubular body, said tubular body having a rigid wall, a flexible wall, said flexible wall being disposed internally of said tubular body and .being sealed at its extremities to the extremities of the interior of said tubula-r body thereby defining a substantially annular chamber, inflow and outflow ports dis- 5 6 posed adjacent the respective extremities of said tubular References Cited by the Examiner body to convey fluid to and from said annular chamber, UNITED STATES PATENTS and eccentric means disposed axially of said tubular body 2,752,860 ,H1956 Waldin 10.3 149 for deforrning said flexible Wall by applying successive radially directive forces to said exible wall to generate 5 FOREIGN PATENTS a wave-like motion in said flexible wall from one of said 637,586 `6/ 1939 Germany. ports toward the other of said ports, said eccentric means 800,154 8/ 1958 Great Britain.

comprising a rotatable shaft, a plurality of eccentrics ixedly mounted on said shaft, ya plurality of annular bea-r- 'DONLEY J- STOCKING Pmmy Examme' ings mounted on said eccentrics, and means coupled t0 10 WARREN E. COLEMAN, LAURENCE V, EFNER, said shaft to impart rotation thereto. Examiners. 

1. A ROTARY PUMP FOR A FLUID, COMPRISING A CYLINDRICAL TUBULAR BODY WHICH IS LONGITUDINALLY TRAVERSED BY A FLEXIBLE TUBULAR DIAPHRAGM DEFINING WITH THIS BODY AN ANNULAR CHAMBER, THE RESPECTIVE ENDS OF WHICH COMMUNICATE WITH AN INLET AND OUTLET ORIFICE FOR A FLUID, MEANS FOR CONTINUOUSLY DEFORMING THE DIAPHRAGM TO CAUSE THE DISPLACEMENT, FROM THE INLET ORIFICE TOWARDS THE OUTLET ORIFICE, OF FLUID CONFINED BETWEEN THE DIAPHRAGM AND THE TUBULAR BODY, AND FURTHER CHARACTERIZED IN THAT SAID MEANS FOR DEFORMING THE DIAPHRAGM ARE CONSTITUTED BY AN HELICOIDAL ROTOR HAVING A CIRCULAR SECTION AND A SERIES OF BEARINGS ECCENTRIC IN RELATION TO THE AXIS OF THE PUMP BODY, SAID BEARINGS BEING ANGULARLY STAGGERED, AND SAID DIAPHRAGM RESTING ON RINGS IN WHICH THE ECCENTRIC BEARINGS OF THE ROTOR CAN ROTATE. 